h4h5tools

Purpose:
    [is this a bug fix? feature? ...]
New feature
Description:
    [describe the bug, or describe the new feature, etc]
Add the support of szip compression and clean up the conversion from other compression method.
Solution:
    [details about the changes, algorithm, etc...]
    [Please as detail as you can since your own explanation is
    better than others guessing it from the code.]
By default, h4toh5 will keep the original settings from HDF4. However, for compression being supported in HDF4
but not in HDF5, h4toh5 will convert them with deflate compression with level 9. This can be changed later to
follow other policies set by HDF group.
Platforms tested:
sol 2.7, Linux 2.4, AIX 5.1
    [machines you have tested the changed version.  This is absolute
    important.  Test it out on at least two or three different platforms
    such as Big-endian-32bit (SUN/IRIX), little-endian-32(LINUX) and
    64-bit (IRIX64/UNICOS/DEC-ALPHA) would be good.]